|Northern Mockingbird at dawn. Waste treatment ponds, Borrego Springs, California. October 29, 106. Greg Gillson.|
Mockingbirds are pretty much found throughout San Diego County except the unbroken chaparral of the foothills and above 4000 feet in the higher mountains. Thus, the range in the county is cut in two by the north-south running mountains.
West of the mountains these are common resident birds in urban and agricultural areas throughout the coastal lowlands.
East of the mountains they breed widely throughout sage, scrub, and cactus habitats, as well as oases and towns. Interestingly, they breed noticeably less widely in the desert in drier years, retreating into desert towns then (Unitt, 2004). And they are less widespread in winter--concentrating near settlements and oases.
Another thing that is interesting about Mockingbirds is that they have a prolonged breeding season. They may breed twice, or sometimes thrice, in a single breeding season. Nests with eggs have been noted in California from late February to the beginning of September.